The parasitic diseases of school children in Lagos State, Nigeria

Transcription

1 The parasitic diseases of school children in Lagos State, Nigeria Autor(en): Objekttyp: Ejezie, G.C. Article Zeitschrift: Acta Tropica Band (Jahr): 38 (1981) Heft 1 PDF erstellt am: Persistenter Link: Nutzungsbedingungen Die ETH-Bibliothek ist Anbieterin der digitalisierten Zeitschriften. Sie besitzt keine Urheberrechte an den Inhalten der Zeitschriften. Die Rechte liegen in der Regel bei den Herausgebern. Die auf der Plattform e-periodica veröffentlichten Dokumente stehen für nicht-kommerzielle Zwecke in Lehre und Forschung sowie für die private Nutzung frei zur Verfügung. Einzelne Dateien oder Ausdrucke aus diesem Angebot können zusammen mit diesen Nutzungsbedingungen und den korrekten Herkunftsbezeichnungen weitergegeben werden. Das Veröffentlichen von Bildern in Print- und Online-Publikationen ist nur mit vorheriger Genehmigung der Rechteinhaber erlaubt. Die systematische Speicherung von Teilen des elektronischen Angebots auf anderen Servern bedarf ebenfalls des schriftlichen Einverständnisses der Rechteinhaber. Haftungsausschluss Alle Angaben erfolgen ohne Gewähr für Vollständigkeit oder Richtigkeit. Es wird keine Haftung übernommen für Schäden durch die Verwendung von Informationen aus diesem Online-Angebot oder durch das Fehlen von Informationen. Dies gilt auch für Inhalte Dritter, die über dieses Angebot zugänglich sind. Ein Dienst der ETH-Bibliothek ETH Zürich, Rämistrasse 101, 8092 Zürich, Schweiz,

2 Acta Tropica National Institute for Medical Research. Yaba. Nigeria The parasitic diseases of school children in Lagos State, Nigeria G. C. Ejezie Summary A survey of 5,595 primary school children in Lagos State showed that most of the children were over-loaded with parasitic infestations which included malaria (37.7%), schistosomiasis (13.4%), ascariasis (74.2%), trichuriasis (75.8%), hookworm (29.5%) and tungiasis (49.5%). Multiple infections were observed with about 16.2% harbouring all the causative organisms of the para sitic diseases enumerated above. The high prevalence of parasitic infestations among these children is an index of the community's low level of health and also of inadequate health education, because most of these diseases are prevent able if the people are told what to do. Key words: primary school pupils; parasitic infestations; inadequate health education. Introduction Parasitic infestations constitute major public health problems in develop ing countries. Most of these parasitoses are preventable, and their high prev alence rates may suggest inadequate preventive measures and/or undue em phasis on cure rather than prevention. This inadequacy could be a consequence of unreliable surveillance data, without which effective control measures would be difficult to achieve. The aim of this study therefore is to provide the much needed information on the epidemiology of the major parasitic infestations which affect the children of this area, as well as the environmental factors contributing to their spread, as a prelude to the planning and execution of effective control measures. Correspondence: Dr. G. Chuks Ejezie. National Institute for Medical Research. P.M.B Yaba. Nigeria 79

3 [bonfton < i /odo- % ya g u s i [tonun ^>tl]anaxir E]ir in Erido Isalu 1«Aqe njar Topo l.b. '\/ \ ~ 1 \^^ LAGOON /LAGOS Y i T"' --" LGAX / \ / ÂT~ \ LAGOS / S^Pv EPE AjequnlV ^-T % L G A Fig. 1. Map of Lagos State of Nigeria. Areas covered by the survey. Materials and methods The area covered by this survey is scattered in 25 villages in and around Epe. Ikorodu. Badagry and Ajegunle areas of Lagos State (Fig. 1). A total of school pupils aged between 6 and 15 years were screened as follows: for urinary schistosomiasis for malaria, trypanosomiasis and filariasis. 810 for intestinal helminths and 600 for tungiasis. The schools were randomly selected from each geographical area of the state1. Thin and thick blood smears were made on the same slide from finger pricks. The smears were dried, stained with Giemsa and examined under the microscope for common blood parasites. The gametocyte rate for malaria parasite was determined using identifiable crescents of P. falciparum (Fasan. 1969). Parasite density was determined by counting the parasites against 400 leucocytes in the same fields as the parasitized red blood cells and their density per mm3 of blood calculated using the method of Bruce-Chwatt 1958). Capillary blood was collected from all the children to determine their packed cell volume (PCV), and haemoglobin concentration was measured on a drop of whole blood by means of a Spencer Haemoglobin Meter (American Optical Co.) and the level read as g/100 ml of blood. Mid-stream urine was collected from the pupils between 10 a.m. and 2 p.m. during the weekly visits. Urine analysis was carried out immediately using Bili-Labstix reagent strips to determine the amount of protein and blood in the urine. 5. haematobium egg counts were made as already de scribed (Ejezie and Ade-Serrano. 1979). Faecal samples collected from the pupils were processed on the spot by the method of Katz et al. (1972). These were examined later under the microscope for helminth ova. For tungiasis. the subjects had their thoroughly washed toes examined for the usual sign of ''white patch w ith a black dot" of the burrowed gravid female Tunga penetrans. Results Bloodfilm examination The results of the blood film examinations are shown in Table % of all the children examined were infected with Plasmodiumfalciparum. The para site density was 1,550 per mm3 of blood with a mean gametocyte rate of 3.1. Both the packed cell volume and the haemoglobin concentration were found to be similar in both age groups. A few of the pupils (0.7%) were infected by Dipe talonema perstans microfilariae. No cases of trypanosomiasis were found. 1 Weekly surveys were conducted in the primary schools from February 1977 to December SO

4 ; ii VLi Vi OSST L'Li 68'Z Eiox/uBapM OOTI STI i'lz 69i VZ [ p oefi OZ.9'1 9'ü 6'6 Z.SO'1 tm'i 6-9 si-oi P" ooi ß uiqoi oui3ej-i %A3d 3JBJ 31ÄDOiaUIE{) cuiui/äjisu3p 31ISEJE(J 3AIlISOd % :sje3uispoo g ON (SJESX) 3 V SlU3IlEd EUE EUI ui dnojs 3 e pue UOI1EJ1U33UO0 uiqo)soui3eq '(A3d) suinjoa po p35ped '3)ej 3i^ooi3tuE 'Aisusp siisejed u33a\iaq diqsuouepy 3)qEX

5 Table 2. Prevalence of urinary schistosomiasis and intensity of the infections in the two age groups studied Age (years) No. Urine analysis: Mean egg Mean Haematuria % positive count ova/ proteinuria % 10 ml urine mg/100 ml Mean/Total Table 3. Distribution of intestinal helminths among the two age groups Age (years) No. Ascaris Trichuris Hookworm Ascaris and Hookworm. % infec % infec % infec Trichuris Ascaris and tion tion tion % infection Trichuris % infection Total Urine examination Eggs of Schistosoma haematobium were found in 13.4% of all the urine samples examined. Local foci of vesicular schistosomiasis were found in Ajara (35.5%), Oto-Ijanikin (25.0%), Epe (8.8%), Ejirin (4.2%) and Ketu (3.4%). The mean egg count was ova/10 ml urine. Mean proteinuria was mg/ 100 ml while 65.2% of all the infected children had haematuria (Table 2). Stool examination Examination of the 810 faecal samples showed that 74.2%, 75.8% and 29.5% were infected by Ascaris lumbrieoides, Trichuris trichiura and hookworm, respectively (Table 3). 60.4% of these were infected by both Ascaris and Trichu ris while 24.3% had all the three parasites. The mean egg load of the ascariasis patients was 2,544 eggs/g faeces, while the value in trichuriasis was 1,752 eggs/g faeces. Where these two occur together in the same host, the mean egg loads were 432 and 24 eggs/g faeces for Ascaris and Trichuris, respectively. 21.2% of these patients had urinary schistosomiasis also. No eggs of 5. mansoni were found. S2

6 Toe examination Of the 339 boys and 261 girls whose toes were screened for tungiasis, 39.5% had the gravid female of Tunga penetrans embedded in their toes. These were made up of 136 boys and 101 girls. The prevalence rate of tungiasis was found to decrease with increasing age, such that at the age of 15 years it has decreased by about 50%. More boys than girls were infested. The records of the local dispen sary showed that 1,773 patients were treated in the previous year. 845 of these (47.7%) were for sores alone. No cases of dracontiasis were observed. Discussion The evidence available from this work shows an intense transmission of a wide variety of parasitic infections among primary school children in this area. There were many cases (16.2%) of multiple infections - the same individuals being infected by Plasmodium falciparum. Schistosoma haematobium, Ascaris lumbrieoides and Trichuris trichiura, all at the same time. The overall malaria parasite rate of 37.7%, with a higher rate among those under 9 years old, is similar to the results of other workers in this holoendemic area (Okpala, 1975). This is, however, lower than the value of 65.9% recorded by Fasan (1969), in this same State. However, most of the villages have rural dis pensaries where antimalarial drugs could be administered. Some anti-malaria activities are in fact being carried out by government agencies in some of the areas covered by this study. The high gametocyte rate of 4.1 observed among the 6-9-year olds suggests that active transmission is still going on and any Chemotherapie control mea sures should be concentrated at this age group. This survey has revealed some other local foci of endemic urinary schisto somiasis in addition to those already known in the State (Okpala, 1961). These are located at Ajara and Oto-Ijanikin. In both these areas, infection is accompa nied by high egg output, proteinuria and haematuria. Although the mortality and morbidity attributable to 5. haematobium infection is low (Ejezie and Ade- Serrano, 1980) high prevalence of urinary schistosomiasis is associated with renal function impairment, and post-treatment studies suggested bladder calci fication and structural lesions of the ureters and kidneys in the affected children of this State (Oyediran, 1976). The examination of faecal samples of the pupils showed that 92.3% were infected with either Ascaris, Trichuris or hookworm. Multiple infections by Ascaris and Trichuris occurred more often probably because both organisms share similar modes of transmission. The double infection is followed by reduced egg output when compared with single infections. The customary habit of indiscriminate defaecation coupled with the eating of contaminated fresh fruits and vegetables with equally contaminated unwashed hands are the prin cipal sources of infection. S3

7 Results from the toe and ankle examination show a high prevalence of sores among the pupils. This finding is confirmed by the records in the local dispensary register. In the absence of any cases of dracontiasis, the ulcers proba bly result from secondary microbial infections of the wounds left by asceptic removal of the Tunga penetrans (Chandler and Read, 1961). Lots of pigs were found to be roaming about in this area. The presence of this animal host proba bly contributes to the prevalence of tungiasis (WHO, 1979). Generally, this work has shown that an average rural primary school pupil in this State (and probably elsewhere in this country) is over-loaded with para sitic infections, most of which are preventable through well-planned and care fully organised health education programmes. Basic sanitation should aim at the provision of safe water, safe environment and a safe place to live for all the people. The high prevalence of parasitic diseases, particularly among children is an index of not only their community's low level of health, but also of inade quate health-education. The school teachers have a tremendous role to play in order to change the situation. Acknowledgment. The technical assistance of Mrs. Theresa Onyechi and Mrs. Chinwe Okerekeocha is hereby acknowledged. Bruce-Chwatt L. J.: Parasite density index in malaria. Trans, roy. Soc. trop. Med. Hyg. 52, 389 (1958). Chandler A. C. Read C. P.: Introduction to parasitology. 10th ed.. p John Wiley & Sons. New York Ejezie G. C. Ade-Serrano M. A.: Schistosoma haematobium in Ajara Community of Badagry: 1. A study of the prevalence, intensity and morbidity from infection among primary school children. Trop, geogr. Med. (in press) (1980). Fasan P. O.: Malaria in the school children of Lagos City and Lagos State. West Afr. med. J (1969). Katz N.. Chaves A.. Pellegrino J.: A simple device for quantitative stool thick-smear technique in schistosomiasis mansoni. Rev. Inst. Med. trop. S. Paulo (1972). Okpala I.: Studies on Schistosoma haematobium infection in school children in Epe. Western Nigeria. West Afr. med. J (1961). Okpala L: The incidence of malaria in school children in Western and East Central States of Nigeria. Paper read at the Scientific Conference on Malaria in Nigeria, p (1975). Oyediran A. BOO.: Renal function in vesical schistosomiasis, p M.D. Thesis. University of Ibadan World Health Organisation: Parasitic zoonoses. WHO Technical Report Series No p. 94 (1979). 84